Prime Minister Prayut Chan-o-cha said on Wednesday that he did not intend to deliver an incomplete oath during the swearing in of his cabinet last month, as the Pheu Thai Party urged him to seek a royal pardon.
Gen Prayut said during his visit to the southern province of Yala that he had not intended to cut short the oath, and people should focus on his intention.
"It will be settled soon because I did not intend to do it wrong. The point is intention," the prime minister said.
Opponents have been targeting the oath ceremony, saying Gen Prayut did not vocalise the last sentence of the oath required by the constitution during the swearing-in on July 16.
Section 161 of the 2017 constitution prescribes: "Before assuming duties, cabinet ministers must swear an oath to His Majesty the King as follows:
"I (name of minister) swear I will be loyal to His Majesty and perform my duties honestly for the benefit of the country and the people. I will also uphold and comply with the constitution of the kingdom in every aspect."
Deputy Prime Minister Wissanu Krea-ngam said on Wednesday he had no idea how the prime minister would solve the issue, and the prime minister had not consulted him on the matter.
He did not answer when reporters asked how the incomplete oath would affect the work of the government.
Mr Wissanu said similar incidents had happened during the swearing-in of a few cabinet ministers appointed after cabinet reshuffles, but never during the ceremony to swear in a whole cabinet. He did not elaborate on the past incidents.
Former justice minister Chaikasem Nitisiri of the opposition-core Pheu Thai Party said Gen Prayut had to admit to the mistake, seek a royal pardon and lead the cabinet to a fresh swearing-in.
"To me, there is no other way out. Other solutions would only lead to other problems... If it is not quickly solved, complaints may be filed with concerned organisations. Gen Prayut and the cabinet may be charged with unconstitutional national administration and face harsher criminal responsibilities," he said.